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PGC-1a, c-MYC and ODC1 expression in the Taylor database

Although tumorigenesis is dependent on the reprogramming of cellular metabolism, the metabolic pathways engaged in the formation of metastases remain largely unknown. The transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) plays a pleiotropic role in the control of cancer cell metabolism and has been associated with a good prognosis in prostate cancer. Here, we show that PGC1α represses the metastatic properties of prostate cancer cells via modulation of the polyamine biosynthesis pathway. Mechanistically, PGC1α inhibits the expression of c-MYC and ornithine decarboxylase 1 (ODC1), the rate-limiting enzyme for polyamine synthesis. Analysis of in vivo metastases and clinical data from patients with prostate cancer support the proposition that the PGC1α/c-MYC/ODC1 axis regulates polyamine biosynthesis and prostate cancer aggressiveness. In conclusion, downregulation of PGC1α renders prostate cancer cells dependent on polyamine to promote metastasis.Significance:These findings show that a major regulator of mitochondrial metabolism controls polyamine synthesis and prostate cancer aggressiveness, with potential applications in therapy and identification of new biomarkers.

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The Wilms’ tumor suppressor Wt1 is involved in multiple developmental processes and adult tissue homeostasis. The first phenotypes recognized in Wt1 knockout mice were developmental cardiac and kidney defects. Wt1 expression in the heart has been described in epicardial, endothelial, smooth muscle cells, and fibroblasts. Expression of Wt1 in cardiomyocytes has been suggested but remained a controversial issue, as well as the role of Wt1 in cardiomyocyte development and regeneration after injury. We determined cardiac Wt1 expression during embryonic development, in the adult, and after cardiac injury by quantitative RT-PCR and immunohistochemistry. As in vitro model, phenotypic cardiomyocyte differentiation, i.e., the appearance of rhythmically beating clones from mouse embryonic stem cells (mESCs) and associated changes in gene expression were analyzed. We detected Wt1 in cardiomyocytes from embryonic day (E10.5), the first time point investigated, until adult age. Cardiac Wt1 mRNA levels decreased during embryonic development. In the adult, Wt1 was reactivated in cardiomyocytes 48 h and 3 weeks following myocardial infarction. Wt1 mRNA levels were increased in differentiating mESCs. Overexpression of Wt1(-KTS) and Wt1(+KTS) isoforms in ES cells reduced the fraction of phenotypically cardiomyocyte differentiated clones, which was preceded by a temporary increase in c-kit expression in Wt1(-KTS) transfected ES cell clones and induction of some cardiomyocyte markers. Taken together, Wt1 shows a dynamic expression pattern during cardiomyocyte differentiation and overexpression in ES cells reduces their phenotypical cardiomyocyte differentiation.

We aimed to evaluate the therapeutic potential of the pan-FGFR inhibitor erdafitinib to treat dedifferentiated liposarcoma (DDLPS). FGFR expression and their prognostic value were assessed in a series of 694 samples of well-differentiated/dedifferentiated liposarcoma (WDLPS/DDLPS). The effect of erdafitinib&mdash, alone or in combination with other antagonists&mdash, on tumorigenicity was evaluated in vitro and in vivo. We detected overexpression of FGFR1 and/or FGFR4 in a subset of WDLPS and DDLPS and demonstrated correlation of this expression with poor prognosis. Erdafitinib treatment reduced cell viability, inducing apoptosis and strong inhibition of the ERK1/2 pathway. Combining erdafitinib with the MDM2 antagonist RG7388 exerted a synergistic effect on viability, apoptosis, and clonogenicity in one WDLPS and two DDLPS cell lines. Efficacy of this combination was confirmed in vivo on a DDLPS xenograft. Importantly, we report the efficacy of erdafitinib in one patient with refractory DDLPS showing disease stabilization for 12 weeks. We provide evidence that the FGFR pathway has therapeutic potential for a subset of DDLPS and that an FGFR1/FGFR4 expression might constitute a powerful biomarker to select patients for FGFR inhibitor clinical trials. In addition, we show that combining erdafitinib with RG7388 is a promising strategy for patients with DDLPS that deserves further investigation in the clinical setting.

Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors, which function as transcription factors. Among them, PPARβ/δ is highly expressed in endothelial cells. Pharmacological activation with PPARβ/δ agonists had been shown to increase their angiogenic properties. PPARβ/δ has been suggested to be involved in the regulation of the angiogenic switch in tumor progression. However, until now, it is not clear to what extent the expression of PPARβ/δ in tumor endothelium influences tumor progression and metastasis formation. We addressed this question using transgenic mice with an inducible conditional vascular-specific overexpression of PPARβ/δ. Following specific over-expression of PPARβ/δ in endothelial cells, we induced syngenic tumors. We observed an enhanced tumor growth, a higher vessel density, and enhanced metastasis formation in the tumors of animals with vessel-specific overexpression of PPARβ/δ. In order to identify molecular downstream targets of PPARβ/δ in the tumor endothelium, we sorted endothelial cells from the tumors and performed RNA sequencing. We identified platelet-derived growth factor receptor beta (Pdgfrb), platelet-derived growth factor subunit B (Pdgfb), and the tyrosinkinase KIT (c-Kit) as new PPARβ/δ -dependent molecules. We show here that PPARβ/δ activation, regardless of its action on different cancer cell types, leads to a higher tumor vascularization which favors tumor growth and metastasis formation.

We previously reported that biphasic calcium phosphate (BCP) microparticles embedded in a blood clot induces ectopic bone formation in mice and repairs a critical femoral defect in rat. The present pilot study aimed to evaluate in dog and in two models of large defects the efficacy of this composite named "blood for reconstruction of bone" (BRB). We show here that BRB is a cohesive biomaterial easy to prepare from dog autologous blood and to mold to fill large bone defects. First in a model of cylindrical femoral condyle defect, the BRB was compared with BCP particles alone. After 8 weeks, this revealed that the amount of mature bone was slightly and significantly higher with BRB than with BCP particles. Second, in a model consisting in a 2 cm-long critical interruptive defect of the ulna, the BRB was compared with autologous bone. After 6 months, we observed that implantation of BRB can induce the complete reconstruction of the defect and that newly formed bone exhibits high regenerative potential. Comparison with the results obtained with autologous bone grafting strongly suggests that the BRB might be an efficient biomaterial to repair large bone defects, as an alternative or in addition to autologous bone. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1842-1850, 2018.

Gene mutation status assessment of tumors has become standard practice in diagnostic pathology. This is done using samples comprising tumor cells but also non-tumor cells, which may dramatically dilute the proportion of tumor DNA and induce false negative results. Increasing sensitivity of molecular tests presently allows detection of a targeted mutation in a sample with a small percentage of tumor cells, but assessment of tumor cellularity remains essential to adequately interpret the results of molecular tests. Comprehensive tumor cell counting would provide the most reliable approach but is time consuming, and therefore rough global estimations are used, the reliability of which has been questioned in view of their potential clinical impact. The French association for quality assurance in pathology (AFAQAP) conducted two external quality assurance schemes, partly in partnership with the French group of oncology cytogenomics (GFCO). The purpose of the schemes was to (1) evaluate how tumor cellularity is assessed on tissue samples, (2) identify reasons for discrepancies, and (3) provide recommendations for standardization and improvement. Tumor cell percentages in tissue samples of lung and colon cancer were estimated by 40-50 participants, on 10 H&E virtual slides and 20 H&E conventional slides. The average difference between lowest and highest estimated percentage was 66. This was largely due to inadequate definition of cellularity, reflecting confusion between the percentage of tumor cells and the percentage of the area occupied by tumor in the assessed region. The widest range of interobserver variation was observed for samples with dense or scattered lymphocytic infiltrates or with mucinous stroma. Estimations were more accurate in cases with a low percentage of tumor cells. Macrodissection of the most homogeneous area in the tissue reduced inter-laboratory variation. We developed a rating system indicating potential clinical impact of a discrepancy. Fewer discrepancies were clinically relevant since the study was conducted. Although semi-quantitative estimations remain somewhat subjective, their reliability improves when tumor cellularity is adequately defined and heterogeneous tissue samples are macrodissected for molecular analysis.

International audience; Ubiquitin domain-containing protein 1 (UBTD1) is highly evolutionary conserved and has been described to interact with E2 enzymes of the ubiquitin-proteasome system. However, its biological role and the functional significance of this interaction remain largely unknown. Here, we demonstrate that depletion of UBTD1 drastically affects the mechanical properties of epithelial cancer cells via RhoA activation and strongly promotes their aggressiveness. On a stiff matrix, UBTD1 expression is regulated by cell-cell contacts, and the protein is associated with β-catenin at cell junctions. Yes-associated protein (YAP) is a major cell mechano-transducer, and we show that UBTD1 is associated with components of the YAP degradation complex. Interestingly, UBTD1 promotes the interaction of YAP with its E3 ubiquitin ligase β-TrCP Consequently, in cancer cells, UBTD1 depletion decreases YAP ubiquitylation and triggers robust ROCK2-dependent YAP activation and downstream signaling. Data from lung and prostate cancer patients further corroborate the in cellulo results, confirming that low levels of UBTD1 are associated with poor patient survival, suggesting that biological functions of UBTD1 could be beneficial in limiting cancer progression.

International audience; Diffuse large B cell lymphoma (DLBCL) is a heterogeneous disease treated with anti-CD20-based immuno-chemotherapy (R-CHOP). We identified that low levels of GAPDH predict a poor response to R-CHOP treatment. Importantly, we demonstrated that GAPDH(low) lymphomas use OxPhos metabolism and rely on mTORC1 signaling and glutaminolysis. Consistently, disruptors of OxPhos metabolism(phenformin) or glutaminolysis (L-asparaginase) induce cytotoxic responses in GAPDH(low) B cells and improve GAPDH(low) B cell-lymphoma-bearing mice survival, while they are low or not efficient on GAPDH(high) B cell lymphomas. Ultimately, we selected four GAPDH(low) DLBCL patients, who were refractory to all anti-CD20-based therapies, and targeted DLBCL metabolism-using L-asparaginase (K), mTOR inhibitor (T), and metformin (M) (called KTM therapy). Three out of the four patients presented a complete response upon one cycle of KTM. These findings establish that the GAPDH expression level predicts DLBCL patients' response to R-CHOP treatment and their sensitivity to specific metabolic inhibitors.

ALK-negative anaplastic large cell lymphoma associated with breast implant (i-ALCL) has been recently recognized as a distinct entity. Among 43 830 lymphomas registered in the French Lymphopath network since 2010, 300 breast lymphomas comprising 25 peripheral T-cell lymphomas (PTCL) were reviewed. Among PTCL, ALK-negative ALCL was the most frequent and all of them were associated with breast implants.Since 2010, all i-ALCL cases were collected from different institutions through Lymphopath. Immuno-morphologic features, molecular data and clinical outcome of 19 i-ALCLs have been retrospectively analyzed.The median age of the patients was 61 years and the median length between breast implant and i-ALCL was 9 years. Most implants were silicone-filled and textured. Implant removal was performed in 17 out of 19 patients with additional treatment based on mostly CHOP or CHOP-like chemotherapy regimens (n = 10/19) or irradiation (n = 1/19). CHOP alone or ABVD following radiation without implant removal have been given in two patients. The two clinical presentations, i.e. effusion and less frequently tumor mass correlated with distinct histopathologic features: in situ i-ALCL (anaplastic cell proliferation confined to the fibrous capsule) and infiltrative i-ALCL (pleomorphic cells massively infiltrating adjacent tissue with eosinophils and sometimes Reed-Sternberg-like cells mimicking Hodgkin lymphoma). Malignant cells were CD30-positive, showed a variable staining for EMA and were ALK negative. Most cases had a cytotoxic T-cell immunophenotype with variable T-cell antigen loss and pSTAT3 nuclear expression. T-cell receptor genes were clonally rearranged in 13 out of 13 tested cases. After 18 months of median follow-up, the 2-year overall survival for in situ and infiltrative i-ALCL was 100% and 52.5%, respectively.In situ i-ALCLs have an indolent clinical course and generally remain free of disease after implant removal. However, infiltrative i-ALCLs could have a more aggressive clinical course that might require additional therapy to implant removal.

HMGA2, CDK4, and JUN genes have been described as frequently coamplified with MDM2 in atypical lipomatous tumor, well-differentiated liposarcoma, and dedifferentiated liposarcoma. We studied the frequency of amplification of these genes in a series of 48 dedifferentiated liposarcomas and 68 atypical lipomatous tumors/well-differentiated liposarcomas. We correlated their amplification status with clinicopathological features and outcomes. Histologically, both CDK4 (P=0.007) and JUN (P=0.005) amplifications were associated with dedifferentiated liposarcoma, whereas amplification of the proximal parts of HMGA2 (5'-untranslated region (UTR) and exons 1-3) was associated with atypical lipomatous tumor/well-differentiated liposarcoma (P=0.01). CDK4 amplification was associated with axial tumors. Amplification of 5'-UTR and exons 1-3 of HMGA2 was associated with primary status and grade 1. Shorter overall survival was correlated with: age >64 years (P=0.03), chemotherapy used in first intent (P

Clinical trials have shown the benefits of FGFR inhibitors; notably, the oral pan-FGFR inhibitor JNJ-42756493 (erdafitinib) has recently been the first FGFR kinase inhibitor to receive US FDA approval for the treatment of patients with advanced or metastatic urothelial carcinoma. Our objectives were to show that the FGFR pathway is involved in liposarcoma (LPS) pathogenesis and to investigate the therapeutic potential of erdafitinib for LPS patients. LPS is the most common soft tissue sarcoma. Among LPS, well-differentiated/dedifferentiated LPS (WD/DDLPS) are the most frequent types. DDLPS have metastatic potential and a poor prognosis with a five-year mortality rate of 30%. Standard chemotherapies are inefficient and new therapeutic options are needed. FRS2, a crucial adaptor protein of the FGFR signaling pathway is overexpressed in most WD/DDLPS suggesting involvement of the FGFR pathway in LPS tumorigenesis. Immunohistochemistry was used to perform an exhaustive analysis of the expression pattern of FGFR1-4 in WD/DDLPS both in a large collection of 421 primary tumors and in our in-house panel of validated human WDLPS and DDLPS cell lines. Cells were exposed to erdafitinib - as a single agent or in combination - and apoptosis and signalling pathway perturbations were monitored by flow cytometry and western blotting. Xenograft mouse models were used to confirm our in vitro results in the in vivo setting. We have detected a high expression of FGFR1 and/or FGFR4 in a significant percentage of WDLPS and DDLPS and demonstrated that this expression is correlated with poor prognosis. Exposure of LPS cells to erdafitinib induced a decrease in cell viability, cell cycle arrest in G1 and apoptosis. Erdafitinib treatment had a strong inhibitory effect on the ERK1/2 pathway whereas the PI3K/AKT pathway was less affected. The PI3K/mTOR antagonist BEZ235 was not synergistic with erdafitinib in DDLPS cells. MDM2 overexpression being the hallmark of WD/DDLPS, we investigated the effects of the MDM2-TP53 interaction inhibitor RG7388 (idasanutlin) in combination with erdafitinib. Interestingly, we found that the combination of RG7388 and erdafitinib exerts a highly synergistic effect on both viability and apoptosis in all our WDLPS and DDLPS cell lines. We are currently investigating the mechanics of the synergy between the FGFR and the MDM2 antagonists. We confirmed the inhibitory effect of erdafitinib on tumor growth using a DDLPS xenograft model. Finally and importantly, we report the efficacy of FGFR inhibition in two metastatic DDLPS patients heavily pretreated and refractory to several lines of treatment with notably one patient on erdafitinib showing stable disease for 15 weeks. In conclusion, we have shown that the FGFR pathway has therapeutic potential for a subset of DDLPS patients and that FGFR expression might constitute a powerful biomarker to select patients for clinical trials testing FGFR inhibitors. Citation Format: Bérengère Dadone-Montaudié, Audrey Laroche-Clary, Aline Mongis, Vanessa Chaire, Ilaria Di Mauro, Renaud Schiappa, Emmanuel Chamorey, Bertucci François, Florence Pedeutour, Finetti Pascal, Jean-François Michiels, Antoine Italiano, Laurence Bianchini. Analysis of the role of FGFR signaling in liposarcomas: Dual targeting of FGFR and MDM2 is synergistic [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5185.

This study investigated the relationship of oxytocin (OT) to chondrogenesis and osteoarthritis (OA). Human bone marrow and multipotent adipose-derived stem cells were cultured in vitro in the absence or presence of OT and assayed for mRNA transcript expression along with histological and immunohistochemical analyses. To study the effects of OT in OA in vivo, a rat model and a human cohort of 63 men and 19 women with hand OA and healthy controls, respectively, were used. The baseline circulating OT, interleukin-6, leptin, and oestradiol levels were measured, and hand X-ray examinations were performed for each subject. OT induced increased aggrecan, collagen (Col) X, and cartilage oligomeric matrix protein mRNA transcript levels in vitro, and the immunolabelling experiments revealed a normalization of Sox9 and Col II protein expression levels. No histological differences in lesion severity were observed between rat OA groups. In the clinical study, a multivariate analysis adjusted for age, body mass index, and leptin levels revealed a significant association between OA and lower levels of OT (odds ratio = 0.77, p = 0.012). Serum OT levels are reduced in patients with hand OA, and OT showed a stimulatory effect on chondrogenesis. Thus, OT may contribute to the pathophysiology of OA.

Optimizing a formulation buffer for biological products such as vaccines or monoclonal antibodies is a complex task. One of the reasons for this is that the number of formulation ingredients make it difficult to cost efficiently design experiments. The FDA’s Process Validation (PV) initiative insists on continuously improving the understanding of manufacturing processes, together with accurately estimating their robustness and reliability. During design and characterization studies, they suggest the derivation of a design space, a concept introduced by the ICH Q8 as “the multidimensional combination and interaction of input variables (e.g., materials attributes) and process parameters that have been demonstrated to provide assurance of quality.” Deriving a design space to optimize multiple quality attributes isn’t easy, and the uncertainty of the estimation is often ignored by scientists and statisticians. Using Bayesian methods to predict future results, and modern design of experiment (DoE) to efficiently explore the complete experimental design, this chapter presents how the quality by design paradigm can be applied to pharmaceutical formulation.

May-Grunwald-Giemsa (MGG) stain is a Romanowsky-type, polychromatic stain as those of Giemsa, Leishman and Wright. Apart being the reference method of haematology, it has become a routine stain of diagnostic cytopathology for the study of air-dried preparations (lymph node imprints, centrifuged body fluids and fine needle aspirations). In the context of their actions of promoting the principles of quality assurance in cytopathology, the French Association for Quality Assurance in Anatomic and Cytologic Pathology (AFAQAP) and the French Society of Clinical Cytology (SFCC) conducted a proficiency test on MGG stain in 2013. Results from the test, together with the review of literature data allow pre-analytical and analytical steps of MGG stain to be updated. Recommendations include rapid air-drying of cell preparations/imprints, fixation using either methanol or May-Grunwald alone for 3-10minutes, two-step staining: 50% May-Grunwald in buffer pH 6.8 v/v for 3-5minutes, followed by 10% buffered Giemsa solution for 10-30minutes, and running water for 1-3minutes. Quality evaluation must be performed on red blood cells (RBCs) and leukocytes, not on tumour cells. Under correct pH conditions, RBCs must appear pink-orange (acidophilic) or buff-coloured, neither green nor blue. Leukocyte cytoplasm must be almost transparent, with clearly delineated granules. However, staining may vary somewhat and testing is recommended for automated methods (slide stainers) which remain the standard for reproducibility. Though MGG stain remains the reference stain, Diff-Quik(®) stain can be used for the rapid evaluation of cell samples.

We previously reported that blood clot combined with biphasic calcium phosphate microparticles constitute a biomaterial (BRB) that can repair a bone critical defect in rat and induces subcutaneous bone formation in mice. The granulocyte colony-stimulating factor (G-CSF) is the agent most commonly used in human to enrich blood with hematopoietic stem and progenitor cells (HSPCs) as well as granulocytes (GCs). Moreover, recent data also suggest that it can mobilize mesenchymal stem cells (MSCs). Here, we asked whether the osteoinductive properties of the BRB could be further enhanced by G-CSF, either by replacing normal blood by G-CSF-mobilized blood (BRBe) or by treating the recipient animals with G-CSF. The experiments performed in C57BL/6 mice showed that G-CSF induces a marked increase of circulating HPCs and GCs, but not of MSCs. BRBe prepared with G-CSF-enriched blood induced a slight but significant decrease of subcutaneous bone formation compared to BRB prepared with normal blood. Additional injection of G-CSF to the recipient mice had no significant effect on the bone formation induced by BRB or BRBe. Altogether these results indicate that, in this model of ectopic implantation, cell mobilization induced by G-CSF has a negative effect on the osteoinductive property of this blood/BCP composite.

Xanthomas are common in cutaneous sites but may also be seen in unusual locations. In view of the paucity of reported cases, the occurrence of such lesions within the breast stroma would appear to be either unusual, underreported, or ignored. Indeed, most reports of the few breast xanthomas and of the even fewer xanthomatous fibroadenomas reported have appeared in the older literature. Herein, a case of fibroadenoma with multiple foci of xanthoma is reported, the literature is briefly reviewed, and the apparent difference between the previous cases and the current case is highlighted.

We previously reported that biphasic calcium phosphate (BCP) microparticles embedded in a blood clot induces ectopic bone formation in mice and repairs a critical femoral defect in rat. The present pilot study aimed to evaluate in dog and in two models of large defects the efficacy of this composite named "blood for reconstruction of bone" (BRB). We show here that BRB is a cohesive biomaterial easy to prepare from dog autologous blood and to mold to fill large bone defects. First in a model of cylindrical femoral condyle defect, the BRB was compared with BCP particles alone. After 8 weeks, this revealed that the amount of mature bone was slightly and significantly higher with BRB than with BCP particles. Second, in a model consisting in a 2 cm-long critical interruptive defect of the ulna, the BRB was compared with autologous bone. After 6 months, we observed that implantation of BRB can induce the complete reconstruction of the defect and that newly formed bone exhibits high regenerative potential. Comparison with the results obtained with autologous bone grafting strongly suggests that the BRB might be an efficient biomaterial to repair large bone defects, as an alternative or in addition to autologous bone. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1842-1850, 2018.

Purpose To prospectively assess the clinical impact of expert review of lymphoma diagnosis in France. Materials and Methods From January 2010 to December 2013, 42,145 samples from patients with newly diagnosed or suspected lymphomas were reviewed, according to the 2008 WHO classification, in real time by experts through the Lymphopath Network. Changes in diagnosis between referral and expert review were classified as major or minor according to their potential impact on patient care. Results The 42,145 reviewed samples comprised 36,920 newly diagnosed mature lymphomas, 321 precursor lymphoid neoplasms, 314 myeloid disorders, and 200 nonhematopoietic neoplasms, with 4,390 benign lesions. There were 4,352 cutaneous and 32,568 noncutaneous lymphomas. The most common mature noncutaneous lymphomas were diffuse large B-cell lymphomas (32.4%), follicular lymphomas (15.3%), classic Hodgkin lymphomas (13%), peripheral T-cell lymphomas (6.3%) of which angioimmunoblastic T-cell lymphomas (2.3%) were the most frequent, and mucosa-associated lymphoid tissue lymphomas (5.8%). A diagnostic change between referral and expert review occurred in 19.7% of patients, with an estimated impact on patient care for 17.4% of patients. This rate was significantly higher for patients sent with a provisional diagnosis seeking expert second opinion (37.8%) than for patients sent with a formal diagnosis (3.7%). The most frequent discrepancies were misclassifications in lymphoma subtype (41.3%), with 12.3% being misclassifications among small B-cell lymphoma entities. Fewer than 2% of changes were between benign and malignant lymphoid conditions. Minor changes (2.3%) mostly consisted of follicular lymphoma misgrading and diffuse large B-cell lymphoma subtype misclassification. Conclusion To our knowledge, this study provides the largest ever description of the distribution of lymphoma entities in a western country and highlights how expert review significantly contributes to a precise lymphoma diagnosis and optimal clinical management in a proportion of patients.

An increasing number of genetically modified mouse models has become available in recent years. Moreover, the number of pharmacological studies performed in mice is high. Phenotypic characterization of these mouse models also requires the examination of cardiac function and morphology. Echocardiography and magnetic resonance imaging (MRI) are commonly used approaches to characterize cardiac function and morphology in mice. Echocardiographic and MRI equipment specialized for use in small rodents is expensive and requires a dedicated space. This protocol describes cardiac measurements in mice using a clinical echocardiographic system with a 15 MHz human vascular probe. Measurements are performed on anesthetized adult mice. At least three image sequences are recorded and analyzed for each animal in M-mode in the parasternal short-axis view. Afterwards, cardiac histological examination is performed, and cardiomyocyte diameters are determined on hematoxylin-eosin- or wheat germ agglutinin (WGA)-stained paraffin sections. Vessel density is determined morphometrically after Pecam-1 immunostaining. The protocol has been applied successfully to pharmacological studies and different genetic animal models under baseline conditions, as well as after experimental myocardial infarction by the permanent ligation of the left anterior descending coronary artery (LAD). In our experience, echocardiographic investigation is limited to anesthetized animals and is feasible in adult mice weighing at least 25 g.

In addition to the TRANSFORMS, FREEDOMS, INFORMS studies, very few publications have identified new cases of skin cancer in patients treated with fingolimod. Here, we present the case of a 52-year-old Caucasian patient with relapsing remitting multiple sclerosis for 19 years, with a phototype II with blue eyes, light brown hair, no personal or family history of melanoma and a low number of naevi (

We have recently described a new nail tumor known as onychocytic matricoma. Herein, we describe its malignant counterpart. Clinically, the tumor simulates onychomatricoma (OM). Histologically, this in situ malignant epithelial tumor exhibits a distinct picture of onychocytic differentiation with signs of both nail matrical differentiation and nail plate differentiation. We have proposed the name onychocytic carcinoma for this singular adnexal neoplasm. Given the peculiar thickening of the nail plate observed in OM, onychocytic matricoma, and onychocytic carcinoma, the clinical individualization of a new type of nail band pattern could be proposed. It presents as an acquired localized (monodactylous) longitudinal pachyonychia. Such longitudinal pachyonychia allow the recognition of the matrical nail tumor, which has a limited etiological spectrum. Xantholeucopachyonychia suggests mainly OM and rarely onychocytic carcinoma. Pachymelanonychia suggests onychocytic matricoma and rarely pigmented OM or onychocytic carcinoma.

We show here that the antidiabetic agents metformin and phenformin and the AMPK activator AICAR exert strong anti-tumoural effects on tPTEN−/− lymphoma cells and on human T-ALL cell lines and primary samples. The compounds act by inhibiting tumour metabolism and proliferation and by inducing apoptosis in parallel with an activation of AMPK and an inhibition of constitutive mTOR. In tPTEN−/− cells, the drugs potentiated the anti-leukaemic effects of dexamethasone, and metformin and phenformin synergised with 2-deoxyglucose (2DG) to impair tumour cell survival. In vivo, metformin and AICAR strongly decreased the growth of luciferase-expressing tPTEN−/− cells xenografted in Nude mice, demonstrating that metabolism targeting could be a potent adjuvant strategy for lymphoma/leukaemia treatment.

International audience; Most lipomas are characterized by translocations involving the HMGA2 gene in 12q14.3. These rearrangements lead to the fusion of HMGA2 with an ectopic sequence from the translocation chromosome partner. Only five fusion partners of HMGA2 have been identified in lipomas so far. The identification of novel fusion partners of HMGA2 is important not only for diagnosis in soft tissue tumors but also because these genes might have an oncogenic role in other tumors. We observed that t(1;12)(p32;q14) was the second most frequent translocation in our series of lipomas after t(3;12)(q28;q14.3). We detected overexpression of HMGA2 mRNA and protein in all t(1;12)(p32;q14) lipomas. We used a fluorescence in situ hybridization-based positional cloning strategy to characterize the 1p32 breakpoint. In 11 cases, we identified PPAP2B, a member of the lipid phosphate phosphatases family as the 1p32 target gene. Reverse transcription-polymerase chain reaction analysis followed by nucleotide sequencing of the fusion transcript indicated that HMGA2 3' untranslated region (3'UTR) fused with exon 6 of PPAP2B in one case. In other t(1;12) cases, the breakpoint was extragenic, located in the 3'region flanking PPAP2B 3'UTR. Moreover, in one case showing a t(1;6)(p32;p21) we observed a rearrangement of PPAP2B and HMGA1, which suggests that HMGA1 might also be a fusion partner for PPAP2B. Our results also revealed that adipocytic differentiation of human mesenchymal stem cells derived from adipose tissue was associated with a significant decrease in PPAP2B mRNA expression suggesting that PPAP2B might play a role in adipogenesis. © 2013 Wiley Periodicals, Inc.

International audience; Mutations in genes coding for mitochondrial helicases such as TWINKLE and DNA2 are involved in mitochondrial myopathies with mtDNA instability in both human and mouse. We show that inactivation of Pif1, a third member of the mitochondrial helicase family, causes a similar phenotype in mouse. pif1-/- animals develop a mitochondrial myopathy with respiratory chain deficiency. Pif1 inactivation is responsible for a deficiency to repair oxidative stress-induced mtDNA damage in mouse embryonic fibroblasts that is improved by complementation with mitochondrial isoform mPif1(67). These results open new perspectives for the exploration of patients with mtDNA instability disorders.

Microinjection of small noncoding RNAs in one-cell embryos was reported in several instances to result in transcriptional activation of target genes. To determine the molecular mechanisms involved and to explore whether such epigenetic regulations could play a role in early development, we used a cell culture system as close as possible to the embryonic state. We report efficient cardiac differentiation of embryonic stem (ES) cells induced by small non-coding RNAs with sequences of Cdk9, a key player in cardiomyocyte differentiation. Transfer of oligoribonucleotides representing parts of the Cdk9 mRNA into ES and mouse embryo fibroblast cultures resulted in upregulation of transcription. Dependency on Argonaute proteins and endogenous antisense transcripts indicated that the inducer oligoribonucleotides were processed by the RNAi machinery. Upregulation of Cdk9 expression resulted in increased efficiency of cardiac differentiation suggesting a potential tool for stem cell-based regenerative medicine.

Background Besides onychomatricoma (OM), which shows a clinical band pattern of nail plate thickening, 2 new onychomatrical tumors with this clinical feature have recently been described: onychocytic matricoma (OCM) and in situ onychocytic carcinoma. Objective The purpose of this study was to present 4 cases of OCMs and compare their clinical and histopathologic characteristics with usual OMs. Methods We studied 4 cases of OCMs with nail clipping in 3 cases and an extensive immunohistochemical study for hair-related keratins and epithelial keratins. Nail clipping of OCMs was compared with the distal nail plate of 5 cases of OMs. Results All cases showed an acquired localized longitudinal band pattern of a thickened nail plate with yellow discoloration in 2 cases and a black streak in 2 cases. All cases showed a V-shaped keratogenous epithelial tumor with a papillomatous pattern of growth. The nail plate was thickened with small holes in a honeycomb pattern. In contrast, the 5 OMs showed the classical pattern of a panonychoma fibropapilliferum. The nail plate showed large cavities in a honeycomb pattern. Conclusions This case series raises awareness of the clinical value of longitudinal pachyonychia coupled with nail clipping in the early detection of onychomatrical tumors as generic diagnosis with a limited differential diagnosis and a simple therapeutic approach. Nail clipping could be an aid in the surgical planning of onychomatrical tumor. A diagnosis of a benign growth could be suggested when the average dimensions of cavities are superior to 0.15 mm sparing the patient from an excisional procedure with its risk of subsequent permanent nail dystrophy. In contrast, nail clipping with a honeycomb pattern of minute cavities with average dimension inferior to 0.10 mm should prompt a biopsy of the distal matrix to rule out a malignant lesion.

Shelterin forms the core complex of telomere proteins and plays critical roles in protecting telomeres against unwanted activation of the DNA damage response and in maintaining telomere length homeostasis. Although shelterin expression is believed to be ubiquitous for stabilization of chromosomal ends, some evidence suggests that some shelterin subunits have tissue-specific functions. However, very little is known regarding how shelterin subunit gene expression is regulated during development and aging. Using two different animal models, the mouse and zebrafish, we reveal herein that shelterin subunits exhibit distinct spatial and temporal expression patterns that do not correlate with the proliferative status of the organ systems examined. Together, this work shows that the shelterin subunits exhibit distinct spatiotemporal expression patterns, suggesting important tissue-specific functions during development throughout the lifespan.

Brown adipose tissue (BAT) is essential for adaptive thermogenesis and dissipation of caloric excess through the activity of uncoupling protein (UCP)-1. BAT in humans is of great interest for the treatment of obesity and related diseases. In this study, the expression of Twik-related acid-sensitive K(+) channel (TASK)-1 [a pH-sensitive potassium channel encoded by the potassium channel, 2-pore domain, subfamily K, member 3 (Kcnk3) gene] correlated highly with Ucp1 expression in obese and cold-exposed mice. In addition, Task1-null mice, compared with their controls, became overweight, mainly because of an increase in white adipose tissue mass and BAT whitening. Task1(-/-)-mouse-derived brown adipocytes, compared with wild-type mouse-derived brown adipocytes, displayed an impaired β3-adrenergic receptor response that was characterized by a decrease in oxygen consumption, Ucp1 expression, and lipolysis. This phenotype was thought to be caused by an exacerbation of mineralocorticoid receptor (MR) signaling, given that it was mimicked by corticoids and reversed by an MR inhibitor. We concluded that the K(+) channel TASK1 controls the thermogenic activity in brown adipocytes through modulation of β-adrenergic receptor signaling.-Pisani, D. F., Beranger, G. E., Corinus, A., Giroud, M., Ghandour, R. A., Altirriba, J., Chambard, J.-C., Mazure, N. M., Bendahhou, S., Duranton, C., Michiels, J.-F., Frontini, A., Rohner-Jeanrenaud, F., Cinti, S., Christian, M., Barhanin, J., Amri, E.-Z. The K(+) channel TASK1 modulates β-adrenergic response in brown adipose tissue through the mineralocorticoid receptor pathway.

PPAR Research, 2016, ISSN:1687-4757, ISSN:1687-4765

Among the tumors of the epidermal appendages, only rare tumors have been proved as differentiating in the direction of the nail. Beside onychomatricoma, we report a new matrical tumor of the nail: onychocytic matricoma (acanthoma of the nail matrix producing onychocytes). The main differential diagnosis of onychocytic matricoma is seborrheic keratosis. However, if attention is paid to the nature of the different layers of the tumor and the peculiar microanatomy of the nail matrix, the differentiation is not difficult. Onychocytic matricoma is a localized (monodactylous) longitudinal melanonychia which is slightly raised. The term pachymelanonychia is used to define the 2 clinical features of the tumor. Pachyonychia indicate a localized thickening of the nail plate, and melanonychia indicate its longitudinal pigmented band. Onychocytic matricoma is composed of a basal compartment with a varying admixture of prekeratogenous cells and keratogenous cells. Endokeratinization originating in the deep portion of the tumor and nests of prekeratogenous and keratogenous cells in concentric arrangement are a characteristic feature. Three major patterns can be identified as follows: acanthotic, papillomatous, keratogenous type with retarded maturation. Given the peculiar thickening of the nail plate observed both in pigmented onychomatricoma and onychocytic matricoma, the term pachymelanonychia longitudinal could be proposed to specify clinically these 2 lesions, which the clinician sometimes mistakes for melanoma.

M. Fevre-Montange, A. Vasiljevic, D. Frappaz, J. Champier, A. Szathmari, M.-H. Aubriot Lorton, F. Chapon, A. Coulon, I. Quintin Roue, M.-B. Delisle, D. Figarella-Branger, A. Laquerriere, C. Miquel, J.-F. Michiels, M. Peoch, M. Polivka, F. Fauchon and A. Jouvet (2012) Neuropathology and Applied Neurobiology38, 87–94 Utility of Ki67 immunostaining in the grading of pineal parenchymal tumours: a multicentre study Aims: Pineal parenchymal tumours (PPTs) are rare neoplasms that are divided into pineocytoma (PC), pineoblastoma (PB) and PPT of intermediate differentiation (PPTID). Factors affecting the survival of patients with PPTs are morphological subtype and histological grading according to mitotic index and neurofilament immunostaining. Grading criteria to distinguish PPTIDs are difficult to define, particularly when using small specimens. The Ki67 labelling index (LI) might be helpful in distinguishing between grade II and III PPTIDs. Our study was performed to assess the predictive value of the Ki67 LI in a large cooperative series of PPTs and to evaluate whether inclusion of this data would improve and refine the World Health Organization classification. Methods: A retrospective analysis of 33 PPTs was performed. The histological features of the tumours were reviewed and Ki67 LI scoring was evaluated by immunohistochemistry. Data were correlated with the patients' survival. Results: The mean Ki67 LI was significantly different for tumour grades (0 in PC, 5.2 ± 0.4 in PPTID grade II, 11.2 ± 2.0 in PPTID grade III, 36.4 ± 6.2 in PB; P